Overview of Liver Cancer / Hepatobiliary Cancer
Hepatobiliary tumors are abnormal growths occurring on or in the liver, bile ducts, and biliary tract, the tubes that carry bile from the liver or gallbladder to the small intestine.
Anatomy of the Liver & Hepatobiliary System
The liver, an organ essential for life, is located on the right side of the abdomen and is protected by the rib cage. It has many functions. The liver:
- cleanses the blood by metabolizing alcohol and other drugs and chemicals, and by neutralizing and destroying poisonous substances
- helps convert food into energy
- manufactures essential body proteins that transport substances in the blood associated with proper blood clotting and resistance to infection
- produces bile, which eliminates toxic substances from the body and aids digestion
- helps to regulates the balance of sex hormones, thyroid hormones, cortisone and other adrenal hormones
- produces, excretes, and converts body cholesterol to other essential substances
- regulates the body's supply of essential vitamins and minerals, such as iron and copper
Incidence and Prevalence of Liver Cancer / Hepatobiliary Cancer
Approximately 1 million new cases of liver and biliary tract cancer are diagnosed around the globe every year. Incidence rates vary by country, although several areas are considered "hotspots." These include China, Japan, and Sub-Saharan Africa. It is believed the high rates in these regions may be associated with hepatitis B and/or mycotoxin contamination of foodstuffs, stored grains, drinking water, and soil.
Tumors of the liver and biliary tract are among the most common tumors worldwide. Approximately 35,660 new cases are diagnosed annually in the United States, resulting in about 24,550 deaths. These new cases include tumors of the gallbladder, tumors of the extrahepatic and intrahepatic biliary ducts, and cancerous growths of the liver called primary hepatocellular carcinomas (HCCs), or primary liver cancer. However, according to a report published in Cancer Research, journal of the American Association for Cancer Research (AACR) in May 2014, liver cancer is expected to become the third-leading cause of cancer-related death in the United States by the year 2030.
In the United States, the average age of liver cancer diagnosis is 60 to 70 years. The disease occurs more frequently in men than in women.
Causes of Liver Cancer / Hepatobiliary Cancer
The most potent hepatocarcinogens are naturally occurring substances. The best studied and most potent of these agents appears to be aflatoxin B1, produced by the fungus aspergillus, which can be found in a variety of stored grains. Other naturally occurring agents include senecio plants and the cycad plants.
Medical conditions associated with HCC include the following:
- Cirrhosis induced by a variety of conditions, such as viral infections of the liver, principally hepatitis B and hepatitis C; excessive alcohol consumption; autoimmune chronic active hepatitis; and cryptogenic cirrhosis—cirrhosis with obscure or unknown origin.
- Metabolic diseases, such as hemochromatosis, a hereditary disease in which the body absorbs too much iron from the diet, resulting in an accumulation of iron in the liver and other organs; glycogen storage diseases; Wilson's disease, a rare hereditary condition in which excessive amounts of copper accumulate in the body; and galactosemia, an inherited disorder in which galactose accumulates in the blood due to a deficiency of an enzyme that catalyzes its conversion to glucose.
Environmental conditions, such as excessive exposure to thorotrast, a contrast agent once used in x-ray exams but now discontinued; androgenic steroids, male sex hormones; and polyvinylchloride, a form of plastic.